Please note that the lack of a December post (in lieu of a monthly post we presented Volume & Series charts for all of 2008) is reflected in the listings above. This has no effect on the data or the rankings, which are derived only from recent site checks, but there are some minor points that are affected; actually, this presents a good opportunity, not only to explain how historical data affects the reports but also to take a closer look at how the reports are formatted.

key:
*rank.* ↕movement (last ranked) : title - pub.info & [score] ::

I've been using this format for these monthly charts for 5 months now (and for more than a year in the weekly reports. No one has complained or asked questions, which is either due to some inate clarity or intuitive formatting (if that's the case I stumbled upon it accidentally, I assure you) or the fact that past the first number and the title most of us don't care.

When there are questions, it usually relates to that last point, the [score] and how it's derived and what it actually means. To answer that: the rankings are comparitive, based on estimates, and the scores come from online 'bestseller' charts -- as explained below.

The bit right after the rank is where historical data is tracked. Usually, the (last ranked) refers to the previous month, but this month I went back to November for the series ranking, and on the volume chart relied on the 2008 yearly numbers.

I include this long aside merely to explain how the Naruto volumes suddenly jumped up hundreds of places; it's not so much that there was a huge surge in just one month -- instead one sees the improvement in sales from late summer and early autumn.

In place of unit sales ("real" data, considered proprietary and a closely held secret of all publishers and retailers) these manga rankings use scores assigned to tiles based on how highly the volumes place on online sales sites' posted "bestseller" lists, or a search of their manga offerings sorted by popularity. The higher the placement, the higher the score, obviously.

Data from bookstores are weighted higher, as are the hourly bestsellers & manga category results from Amazon.

Math Note: In place of point totals in the thousands and thousands, series scores use a formula that sets the No. 1 (Naruto, currently) at 100 points, with everyone else scoring some fraction of that. (it's a straight scalar so all scores are still proportional)

Matt Blind is a bookseller: that's his day job, working as an asst. manager at a far-flung outpost of one of the big box chains. He is also a big fan of manga, has been a blogger of one stripe or another since aught-four, drinks too much, and remembers enough discrete math from his classes at Georgia Tech to construct the truly frightening spreadsheet that spits out these charts.

Matt maintains his own site at RocketBomber.com where he occasionally posts manga reviews, book retail & publishing news, and commentary on fandom in general -- but mostly wastes his time (and yours) with posts on the ever-changing variations and derivatives of these manga charts.

Readers with questions, comments or corrections should email Matt at, not surprisingly, matt[at]rocketbomber[dot]com.